Question

решите неравенство 2cos(pi//2+x)=(корень из 3)tgx

Answer 1

$2 \cos{(\frac{\pi}{2}+x)}= \sqrt{3} tg\, x \\\\ -2\sin x=\sqrt{3} \frac{\sin{x}}{\cos{x}} \\ \\ 2 \sin x \cos{x}=-\sqrt{3}\sin{x} \\ \\ 2 \sin x \cos{x}+\sqrt{3}\sin{x}=0 \\ \\ \sin x \cdot (2 \cos x+ \sqrt{3})=0 \ \\ \sin x=0; \ \ \boxed{x_1=\pi n, n \in Z} \\ \\ 2\cos x + \sqrt{3} =0; \ \ \ \cos x =-\frac{\sqrt{3}}{2} \\ \boxed{x_{2,3} = \pm \frac{5 \pi }{6}+2\pi n, \ n \in Z}$